bad cams is a VERY bad problem
the only thing worse is soft cranks or soft rods
when cams break, if they break in 2 places, thats a big chunk of steel that has to make it past the spinning crank w/o hitting anything … if it gets between the crank and block its instant catastophic engine failure
i once saw one of the early 80’s 60* 173ci engines (IIRC) that blew apart from the same problem, a section of the crank was hanging out the side of the block
it doesnt help that cams are relativly soft to begin with, its usualy pretty easy to give one a wack on the ground and break it in 2 or 3 places